Why would you have die off, Oxy?It's a matter of preference, there isn't a correct answer on this. That is why you will get mixed opinions.
If the rock is fresh from the ocean and hasn't been at the lfs very long, then some die off of critters may still be happening (e.g. sponges, tunicates, etc.). If you place this rock into your tank, then you may get an ammonia spike, so many will not recommend doing so. Alternatively, you can place it in a bucket with a pump if you'd like, and you can test the water until the water doesn't read any more ammonia levels before placing it in your tank.
If the rock is cured, then all life should be already dead and off the rock. You can place it in your tank w/o worry of creating an ammonia spike
In both cases above, you risk bringing in hitchhikers. This matters to some people and not to other people. If you have concerns you can QT it for a bit.
Yes, helpful, indeed.When rock is taken from the ocean, it tends to be packed in wet newspaper (or just piled up in a container) w/o water. Since it is sitting for some time out of water, a lot of soft organisms start to die and then decay. Often times if you pick up live rock that was recently taken from the ocean or shipped, there tends to be some level of die off that can mess with your water quality.
I always rinse off dry rock in rodi water to get any dust or little broken bits from it.
Does this help?
http://www.liveaquaria.com/PIC/article.cfm?aid=209
http://www.pacificeastaquaculture.com/curing_rock.asp
http://www.marinedepot.com/md_LiveRock.html
Thank you.I'd look over all the rock you get closely for any mushy dead items. If it has any, it doesn't hurt to cure it a little in a bucket before it goes in your tank.
As for the rock you rescued -- I'm not sure what you mean by sitting out in the elements? If you mean outside, just make sure that it hasn't come into contact with any chemicals, fertilizers, or pesticides. If so, I wouldn't use it in the tank. Otherwise, a good rinse and soak over night in rodi water and a good shake in the water prior to going into the tank should be fine.